In hospitals, nursing homes, schools, and other institutions, the floors are frequently covered with white or light-colored polyvinylchloride-based material in sheet form or in the form of tiles. To prevent the spreading of disease among the inhabitants of the building, the light-colored polyvinylchloride-covered floors are regularly mopped with a disinfectant-detergent solution which is effective against a broad spectrum of gram negative and gram positive bacteria, and which is virucidal and fungicidal, as well as a deodorant. The active ingredients in the disinfectant solutions of this invention are quaternary ammonium salts such as alkyl and aryl substituted ammonium chlorides.